Have 2002 Civic with wipers that exceed the proper sweep range, slapping on the up and slapping on the down in the rain. When at idle, the sweep is correct. Out on the road in the rain, slap, slap, slap, just like vacuum wipers usta do when you take your foot off the gas. What do ya thing that’s about? How to fix? Thanks.

You might want to check if the splines for the wiper arms are striped out.

Lift the plastic caps on the wiper arms to expose the mounting nuts, remove the nuts and remove the wiper arms from their shafts. Check if the splines are striped out. If they are, the wiper arms need replacement.